U.S Patent No. 2,885,787 discloses a method of measuring thickness in an apparatus for grading objects such as boards and the like on the basis of thickness. In this known apparatus, each board can be passed between a rotatable roller and a restraint. One of these two members is arranged for movement and is urged towards the other member under the influence of a force. The displacement of the rotatable roller resulting from the passage, of the board is a measure for the thickness of the board. Their known measuring method referred to above provides a grading according to class of thickness. In the present invention, the drive of the rotatable roller prevents the object to be measured from being damaged and from losing its straight orientation.
A further factor which determines the quality of the flower is the straightness of the stem.